KR20180044396A - Separation method of brittle substrate - Google Patents

Abstract

A blade edge 51 having a side PS extending from the projection PP and the projection PP and having a convex shape is disposed on one side SF1 of the brittle substrate 4 from the projection PP to the side PS The trench line TL having a groove shape is formed by causing plastic deformation on one surface SF1. A crack line CL is formed by extending a crack of the brittle substrate 4 along at least a part of the trench line TL. The brittle substrate 4 is divided along the crack line CL. The forming process of the trench line TL is the same as the direction in which the crack line CL is extended along the trench line TL in the process of forming the crack line CL in the direction in which the trench line TL is formed .

Description

Separation method of brittle substrate

The present invention relates to a method of breaking a brittle substrate.

It is often necessary to divide a brittle substrate such as a glass substrate in the production of an electric device such as a flat display panel or a solar cell panel. First, a scribing line is formed on the substrate, and then the substrate is divided along the scribing line. The scribe line can be formed by mechanically processing the substrate using a cutter. The cutter slides or rolls on the substrate to form a trench by plastic deformation on the substrate and a vertical crack is formed below the trench. Thereafter, a stress imparting called a braking process is performed. By fully advancing the crack in the thickness direction by the breaking process, the substrate is divided.

The step of dividing the substrate is often performed immediately after the step of forming the scribe line on the substrate. However, it has also been proposed to perform a step of machining a substrate between a step of forming a scribe line and a step of breaking. The step of processing the substrate is, for example, a step of forming any member on the substrate.

For example, according to the technique of International Publication No. 2002/104078, in the method of manufacturing an organic EL display, a scribe line is formed on a glass substrate for each region to be an organic EL display before mounting a sealing cap. Therefore, when the scribe line is formed on the glass substrate after the sealing cap is formed, contact between the sealing cap and the glass cutter can be avoided.

Further, according to the technique of International Publication No. 2003/006391, for example, in the method of manufacturing a liquid crystal display panel, two glass substrates are bonded after a scribe line is formed. Thus, two brittle substrates can be simultaneously braked by a single braking process.

International Publication No. 2002/104078 International Publication No. 2003/006391

According to the above conventional technique, machining into a brittle substrate is carried out after formation of the scribe line, and thereafter, the braking process is performed by stress application. This means that a vertical crack already exists at the time of processing into the brittle substrate. An additional extension in the thickness direction of the vertical cracks is unintentionally generated during processing, so that the brittle substrate, which is supposed to be a single piece during processing, may be divided. Further, even when the substrate processing step is not performed between the scribing line forming step and the substrate breaking step, it is usually necessary to carry or store the substrate after the scribing line forming step and before the substrate breaking step At that time, the substrate may be unintentionally divided. Therefore, it is very useful if the position at which the brittle substrate is divided can be defined by a line that does not involve a vertical crack (in other words, a line in a " crackless state " Further, even if the unintentional division as described above is unnecessary, if the position at which the brittle substrate is divided can be defined by a line not accompanied by a vertical crack, the brittle substrate A smaller load that pushes the blade tip is sufficient. The reduction of the load at the blade tip is useful for alleviating wear of the blade tip or damage to the surface of the brittle substrate. However, a technique of forming a line that does not involve vertical cracks, which can define a position where the brittle substrate is to be divided, by using the sliding of the edge has not been thoroughly studied so far. On the contrary, it has been common that the line which does not involve vertical cracks is recognized only by a simple defective line due to lack of load on the blade edge.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and an object of the present invention is to provide a method of dividing a brittle substrate, in which a position where a brittle substrate is divided can be defined by a line not accompanied by a vertical crack .

The breaking method of the brittle substrate according to one aspect of the present invention has the following steps a) to c).

a) By causing plastic deformation on one surface by sliding a projection having a projection extending from the projection and a side having a convex shape on one surface of the brittle substrate in a direction from the projection to the side, Trench lines are formed. The trench line is formed so as to obtain a crackle state in a state where the brittle substrate is continuously connected in the direction crossing the trench line, below the trench line.

b) a crack line is formed by extending a crack of the brittle substrate along at least a portion of the trench line. Below the trench line by the crack line, the brittle substrate is disconnected continuously in the direction crossing the trench line.

c) The brittle substrate is divided along the crack line.

The step a) is carried out so that the direction in which the crackline extends along the trench line in the step b) becomes the same as the direction in which the trench line is formed.

The breaking method of the brittle substrate according to another aspect of the present invention has the following steps a) to c).

a) By causing plastic deformation on one surface by sliding a projection having a projection extending from the projection and a side having a convex shape on one surface of the brittle substrate in a direction from the side toward the projection, Trench lines are formed. The trench line is formed so as to obtain a crackle state in a state where the brittle substrate is continuously connected in the direction crossing the trench line, below the trench line.

b) a crack line is formed by extending a crack of the brittle substrate along at least a portion of the trench line. Below the trench line by the crack line, the brittle substrate is disconnected continuously in the direction crossing the trench line.

c) The brittle substrate is divided along the crack line.

Step a) is carried out such that the direction in which the crackline extends along the trench line in step b) is opposite to the direction in which the trench line is formed.

According to the present invention, as a line defining the position where the brittle substrate is divided, a trench line having no crack is formed under the line. The crack line to be used as a direct indicator of division is formed by expanding the crack accordingly after formation of the trench line. Thus, the position where the brittle substrate is divided can be defined by a line not accompanied by a vertical crack.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a side view (A) schematically showing the structure of a mechanism used in a method of dividing a brittle substrate according to Embodiment 1 of the present invention, and Fig. 1 (B) schematically shown at the time.
Fig. 2 is a flow chart schematically showing a configuration of a brittle substrate cutting method according to the first embodiment of the present invention. Fig.
3 is a top view schematically showing a first step of a brittle substrate cutting method according to Embodiment 1 of the present invention.
4 is a cross-sectional view schematically showing the configuration of a trench line formed in the method of dividing a brittle substrate according to the first embodiment of the present invention.
5 is a top view schematically showing a second step of a brittle substrate breaking method according to Embodiment 1 of the present invention.
Fig. 6 is a cross-sectional view schematically showing the configuration of a crack line formed in the method for separating a brittle substrate according to the first embodiment of the present invention. Fig.
7 is a top view schematically showing a first step of a brittle substrate cutting method according to the first modification of Embodiment 1 of the present invention.
8 is a top view schematically showing a second step of the brittle substrate breaking method according to the first modification of the first embodiment of the present invention.
9 is a top view schematically showing one step of a brittle substrate cutting method according to a second modification of Embodiment 1 of the present invention.
10 is a top view schematically showing a first step of a brittle substrate breaking method according to Embodiment 2 of the present invention.
Fig. 11 is a top view schematically showing a second step of the brittle substrate breaking method according to the second embodiment of the present invention. Fig.
12 is a top view schematically showing a third step of the bifurcating board breaking method according to the second embodiment of the present invention.
13 is a top view schematically showing one step of a brittle substrate cutting method according to a modification of the second embodiment of the present invention.
14 is a top view schematically showing one step of a brittle substrate cutting method according to Embodiment 3 of the present invention.
15 is a top view schematically showing a first step of a brittle substrate breaking method according to Embodiment 4 of the present invention.
16 is a top view schematically showing a second step of the brittle substrate breaking method according to the fourth embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and the description thereof will not be repeated.

≪ Embodiment 1 >

(Configuration of Cutting Mechanism)

1, the structure of the cutting mechanism 50 used in the step of forming the trench line in the method of cutting the glass substrate 4 (brittle substrate) of the present embodiment will be described first. The cutting mechanism 50 has a blade tip 51 and a shank 52. The blade tip 51 is held by being fixed to the shank 52 as its holder.

A plurality of surfaces surrounding the ceiling surface SD1 (first surface) and the ceiling surface SD1 are formed in the blade 51. These plural surfaces include a side surface SD2 (second surface) and a side surface SD3 (third surface). The topsurface SD1 and the side surfaces SD2 and SD3 (first to third sides) face in different directions and are adjacent to each other. The blade tip 51 has a vertex at which the top face SD1 and the side faces SD2 and SD3 join together and forms the protruding portion PP of the blade tip 51 by the vertex. The side faces SD2 and SD3 form a ridge constituting the side portion PS of the blade edge 51. [ The side portion PS extends linearly from the projection PP. Further, the side portion PS has a convex shape extending in a linear shape at the ridgeline point as described above.

The blade edge 51 is preferably a diamond point. That is, the blade tip 51 is preferably made of diamond in that it can reduce the hardness and the surface roughness. More preferably, the blade edge 51 is made of a single crystal diamond. More preferably, the crystallographic plane SD1 is the {001} plane and each of the sides SD2 and SD3 is the {111} plane. In this case, the side faces SD2 and SD3 are crystallographic and mutually equivalent crystal faces, though they have different directions.

Further, a diamond other than a single crystal may be used. For example, a polycrystalline diamond synthesized by a CVD (Chemical Vapor Deposition) method may be used. Alternatively, a sintered diamond obtained by bonding polycrystalline diamond particles sintered with fine particles of graphite or non-graphitized carbon, which does not contain a binding material such as an iron family element, with a binding material such as an iron family element may be used.

The shank 52 extends along the axial direction AX. The blade tip 51 is preferably attached to the shank 52 such that the normal direction of the surface SD1 generally follows the axial direction AX.

(Method of dividing glass substrate)

In this embodiment, description will be given of a method of dividing the glass substrate 4 (Fig. 2) including a step of sliding the blade tip 51 (Fig. 1) in the direction DA on the upper surface SF1 of the glass substrate 4 do.

The glass substrate 4 to be divided has an upper face SF1 (one face) and an opposite lower face SF2 (another face). Referring to Fig. 3, the edge surrounding the upper surface SF1 includes a side ED1 (first side) and a side ED2 (second side) facing each other. In the example shown in Fig. 3, the edges are rectangular. Therefore, the sides ED1 and ED2 are parallel sides. In the example shown in Fig. 3, the sides ED1 and ED2 are short sides of a rectangle. The glass substrate 4 has a thickness direction DT perpendicular to the upper surface SF1.

Referring to Figs. 2 and 3, a trench line TL is formed at step S30. Specifically, the following steps are performed.

First, the projection PP and the side PS of the blade tip 51 are pushed at the position N1 on the upper surface SF1. Details of the position N1 will be described later. 1 (A), the projecting portion PP of the blade tip 51 on the upper surface SF1 of the glass substrate 4 is placed between the side ED1 and the side PS And the side PS of the blade 51 is arranged between the projection PP and the edge ED2.

Next, the extruded edge 51 is slid on the upper surface SF1 of the glass substrate 4 (see arrows in Fig. 3). The blade tip 51 (Fig. 1) is slid on the upper surface SF1 in the direction DA from the projection PP to the side PS. In other words, the blade point 51 is slid in the direction DA in which the direction from the projection PP to the side portion PS is projected onto the upper surface SF1. The direction DA generally follows the direction in which the extending direction of the side portion PS in the vicinity of the projection PP is projected onto the upper surface SF1. Plastic deformation occurs on the upper surface SF1 by this sliding. Thus, a trench line TL (five lines in the figure) having a groove shape is formed on the upper surface SF1. As described above, the trench line TL is generated by the plastic deformation of the glass substrate 4, and this plastic deformation is sufficiently formed at a low load without shaving the surface of the glass substrate. However, even if the glass substrate 4 is slightly shaved good. However, it is preferable that such a cut-off does not occur in that it can generate undesirable fine debris.

The formation of the trench line TL is performed between the positions N1 and N3. A position N2 is located between the positions N1 and N3. Therefore, the trench line TL is formed between the positions N1 and N2 and between the positions N2 and N3.

The positions N1 and N3 may be located apart from the edge of the upper surface SF1 of the glass substrate 4 as shown in Fig. 3, or one or both of them may be located at the edge of the upper surface SF1. The trench line TL to be formed is apart from the edge of the glass substrate 4 in the case of electrons and in contact with the edge of the glass substrate 4 in the latter case.

Position N1 of positions N1 and N2 is closer to edge ED1 and position N2 of positions N1 and N2 is closer to edge ED2. 3, the position N1 is close to the side ED1 of the sides ED1 and ED2, the position N2 is close to the side ED2 of the sides ED1 and ED2, but both the positions N1 and N2 are close to either the sides ED1 or ED2 .

When the trench line TL is formed, in the present embodiment, the blade tip 51 is displaced from the position N1 to the position N2 and further displaced from the position N2 to the position N3. That is, referring to Fig. 1, the blade edge 51 is displaced in the direction DA from the side ED1 toward the side ED2. The direction DA corresponds to the direction in which the axial direction AX extending from the blade edge 51 is projected onto the upper surface SF1. In this case, the blade tip 51 is pulled by the shank 52 on the upper surface SF1.

4, the step of forming the trench line TL is a step of forming the glass substrate 4 in the extending direction of the trench line TL (the lateral direction in Fig. 3) and the extending direction of the trench line TL below the trench line TL So as to obtain a crackle state in a state in which they are continuously connected to each other in the crossing direction DC. In the cracked state, the trench line TL due to plastic deformation is formed, but no crack is formed. Therefore, even when an external force such as a bending moment is simply applied to the glass substrate 4 as in the conventional breaking process, division along the trench line TL does not easily occur. Therefore, in the uncracked state, the division process along the trench line TL is not performed. In order to obtain a cracked state, the load applied to the blade 51 is small enough to prevent cracking during scribing, and plastic deformation such as to produce an internal stress state capable of generating a crack in a subsequent step It is adjusted so as to occur.

The crackle state can be maintained over a desired time. In order to maintain the cracked state, an operation of applying excessive stress to the glass substrate 4 in the trench line TL, for example, application of a large external stress such as causing breakage of the substrate or a large temperature change So long as the heating can be avoided. In the meantime, the glass substrate 4 may be transported, stored, or processed. The processing of the glass substrate 4 may be a step of forming a member (not shown) on the glass substrate 4, for example.

5, a crack of the glass substrate 4 in the thickness direction DT is stretched along at least a part of the trench line TL in step S50 (Fig. 2) after step S30 (Fig. 2) . 5, a crack of the glass substrate 4 is extended along the portion between the position N2 and the position N3 in the formed trench line TL (Fig. 3). Whereby a crack line CL is formed.

In this embodiment, the formation of the crack line CL starts with the fact that the assist line AL crossing the trench line TL at the position N2 is formed. The assist line AL may be a normal scribe line accompanied by a crack in the thickness direction DT and releases the distortion of the internal stress in the vicinity of the trench line TL. The method of forming the assist line AL is not particularly limited, but it may be formed with the edge of the upper surface SF1 as a starting point, as shown in Fig.

6, the glass substrate 4 below the trench line TL by the crack line CL is tilted in the direction intersecting the extending direction (the lateral direction in Fig. 5) of the trench line TL The continuous connection is disconnected. Here, " continuous connection " means, in other words, a connection that is not blocked by a crack. Further, in the state where the continuous connection is broken as described above, the portions of the glass substrate 4 may be in contact with each other through the cracks of the crack line CL. Also, a slight continuous connection may be left directly under the trench line TL.

In the present embodiment, the direction in which the crack line CL (FIG. 5) extends (broken arrow in FIG. 5) along the trench line TL (FIG. 3) The solid line arrow of FIG. In order to select the extension direction of the crack line CL as such, the method of forming the trench line TL may be appropriately selected.

According to the study by the present inventor, when the trench line TL is formed by sliding in the direction DA of the blade edge 51 (Fig. 1) as in the present embodiment, The extension direction of the crack line CL becomes the same as the extension direction of the trench line TL when the top surface SF1 of the substrate 4 is close to the vertical direction. When the trench line TL is formed by sliding in the direction DA of the blade tip 51 (Fig. 1) as in the present embodiment, the axial direction AX is formed on the glass substrate 4 The extension direction of the crack line CL is opposite to the extension direction of the trench line TL if the slope is inclined largely from the normal direction of the upper surface SF1. If the axial direction AX is at these intermediate angles, the extension direction of the crack line CL becomes unstable, and the prediction becomes difficult.

Therefore, in order to more surely make the extension direction of the crack line CL equal to the formation direction of the trench line TL, the angle of the axial direction AX (FIG. 1) is more perpendicular to the upper surface SF1 The posture of the blade 51 may be adjusted. In other words, by increasing the angle AG1 between the upper surface SF1 and the side surface SD3 and decreasing the angle AG2 between the upper surface SF1 and the top surface SD1, The extension direction can be the same as the extension direction of the trench line TL.

As described above, when the posture of the blade 51 (Fig. 1) is adjusted, the angle AG1 increases and the angle AG2 decreases. According to the first experiment using the edge 51 having an angle of 158 between the top face SD1 and the side face PS, when the angle AG1 = 5 占 and the angle AG2 = 17 占, the extension of the crack line CL The direction was opposite to the extension direction of the trench line TL. The extension direction of the crack line CL becomes equal to the extension direction of the trench line TL when the angle AG1 = the angle AG2 = 11 degrees by adjustment of the axial direction AX. According to the second experiment using the edge 51 having an angle of 165 between the top surface SD1 and the side surface PS, when the angle AG1 = 5 占 and the angle AG2 = 10 占 the extension of the crack line CL The direction was opposite to the extension direction of the trench line TL. The extension direction of the crack line CL becomes equal to the extension direction of the trench line TL by setting the angle AG1 = 7 DEG and the angle AG2 = 8 DEG by adjusting the axial direction AX. It is desirable that the projecting portion PP of the blade edge 51 should have a certain degree of sharpness so that the angle between the topsheet SD1 and the side surface PS is preferably about 160 DEG or less. Under such a condition, it is preferable to set the angle AG2 to the angle AG2 in order to make the extension direction of the crack line CL equal to the extension direction of the trench line TL.

6) along the trench line TL from the position N2 toward the position N3 (see the dashed arrow in Fig. 5) along the trench line TL when the extension direction of the crack line CL is selected as described above A crack of the glass substrate 4 in the glass substrate 4 is expanded. Further, the crack line CL is hardly formed in the direction from the position N2 to the position N1, as compared with the direction from the position N2 to the position N3. In other words, there is a direction dependency in easiness of extension of the crack line CL. Therefore, there may occur a phenomenon that the crack line CL is formed between the positions N2 and N3 and is not formed between the positions N2 and N1. The present embodiment aims at the division of the glass substrate 4 along the positions N2 and N3 and does not aim at the separation of the glass substrate 4 along the positions N2 and N1. Therefore, it is necessary that the crack line CL be formed between the positions N2 and N3, but the difficulty of forming the crack line CL between the positions N2 and N1 is not a problem.

Next, in step S60 (Fig. 2), the glass substrate 4 is divided along the crack line CL. Namely, a so-called brake process is performed. The breaking process can be performed, for example, by application of an external force to the glass substrate 4. [ For example, by applying a stress applying member onto the lower face SF2 toward the crack line CL (Fig. 6) on the upper face SF1 of the glass substrate 4, the crack line CL As shown in Fig. When the crack line CL is completely advanced in the thickness direction DT at the time of its formation, the formation of the crack line CL and the division of the glass substrate 4 can occur at the same time.

As a result, the glass substrate 4 is divided. The above-described crack line CL forming process is essentially different from the so-called break process. In the breaking process, the already formed crack is further extended in the thickness direction to completely separate the substrate. On the other hand, the step of forming the crack line CL causes a change from a crackle state obtained by forming the trench line TL to a state having a crack. It is considered that this change is caused by the opening of the internal stress of the crackle state. The state such as the size and direction of the internal stress generated by the plastic deformation at the time of forming the trench line TL and the formation of the trench line TL is the same as in the case where the rotation of the rotary blade is used, In the case where sliding of the blade edge is used, it is considered to be different. When sliding of the blade edge is used, cracks tend to occur in a wider scribe condition. In addition, stress is required as an instrument to open the internal stress. In the present embodiment, the formation of the assist line AL serves as such an instrument.

In the above description, the upper surface SF1 is flat, but the upper surface may be curved. Although the case where the trench line TL is linear is described, the trench line may have a curved shape. The brittle substrate may be made of a brittle material other than glass and may be made of ceramics, silicon, a compound semiconductor, sapphire or quartz, for example. have.

(effect)

According to the present embodiment, as a line defining the position where the glass substrate 4 is divided, a trench line TL (Fig. 4) having no cracks is formed below the line. The crack line CL (FIG. 6) to be used as a direct instrument of division is formed by extending a crack along the trench line TL after formation thereof. Thus, the position where the glass substrate 4 is divided can be defined by the trench line TL which is a line which does not involve vertical cracks.

As described above, the trench line TL, which is a line that does not involve vertical cracks, can be formed even if the load to push the blade tip 51 with the glass substrate 4 is relatively small as compared with a normal scribe line involving vertical cracks easy. The reduction of the load on the blade tip 51 is useful for alleviating wear of the blade tip 51 or damage to the upper surface SF1 of the glass substrate 4. [

Also, when the blade 51 is slid toward the direction DA (FIG. 1) as in the present embodiment, local wear of the blade 51 is less likely to occur than when the blade 51 slides toward the direction DB . Thus, the life of the blade 51 becomes longer.

The glass substrate 4 (Fig. 3) after the formation of the trench line TL and before the formation of the crack line CL is defined by the trench line TL at the position where the glass substrate 4 is divided, Since the crack line CL has not been formed yet, the fracture is not easily generated. By using this state, it is possible to prevent the glass substrate 4 from being unintentionally divided before the time when the glass substrate 4 is to be divided, while stipulating the position at which the glass substrate 4 is divided. For example, it is possible to prevent the glass substrate 4 from being unintentionally divided during transportation. In addition, it is possible to prevent the glass substrate 4 from being unintentionally divided during any processing on the glass substrate 4.

In the present embodiment, unlike the second embodiment described later, the assist line AL (FIG. 5) is not yet formed at the time when the trench line TL is formed (FIG. 3). Therefore, the crackle state can be more stably maintained without the influence from the assist line (AL).

(First Modification)

Referring to Fig. 7, in the first modification, when the moment of initiation of formation of the crack line CL (Fig. 5) is not sufficiently obtained at the intersection of the assist line AL and the trench line TL at the position N2 . 8, cracks in the thickness direction DT are exerted along the assist line AL by applying an external force to the glass substrate 4 to generate a bending moment or the like. As a result, 4) are separated. With this as a trigger, the formation of the crack line CL is started. According to this modification, the crack line CL can be more reliably formed from the trench line TL.

In this modification, the distortion of the internal stress in the vicinity of the trench line TL is released by the separation of the glass substrate 4, and thereby the formation of the crack line CL is started. Therefore, the assist line AL itself may be a crack line CL formed by stressing the trench line TL.

7, the assist line AL is formed on the upper surface SF1 of the glass substrate 4. However, the assist line AL may be formed on the lower surface SF2. In this case, the assist line AL and the trench line TL cross each other at the position N2 in the plan layout, but do not make direct contact with each other.

(Second Modification)

9, in the second modification, when the trench line TL is formed in step S30 (FIG. 2), the edge 51 is formed on the upper surface SF1 of the glass substrate 4 in comparison with the position N3 And is pushed to a greater force at position N2. Specifically, when the position N4 is located between the positions N3 and N2 and the formation of the trench line TL reaches the position N4, the load on the blade tip 51 is reduced. In other words, the load of the blade tip 51 is higher than the position N3 between the positions N1 and N4, which are the start ends of the trench line TL. This makes it easier to cause the formation of the crack line CL from the position N2 while reducing the load at the portion other than the leading end portion.

≪ Embodiment 2 >

The method of dividing the glass substrate 4 in the present embodiment will be described below with reference to Figs. 10 to 12. Fig.

Referring to Fig. 10, in this embodiment, an assist line AL is formed before formation of the trench line TL, unlike the first embodiment. The method of forming the assist line AL itself is the same as that of Fig. 5 (Embodiment 1).

11, next, the blade tip 51 is pushed against the upper surface SF1 in step S20 (Fig. 2), and the trench line TL is formed in step S30 (Fig. 2). The formation method of the trench line TL itself is the same as that of Fig. 3 (Embodiment 1). The assist line (AL) and the trench line (TL) cross each other at the position N2.

Next, referring to Fig. 12, the glass substrate 4 is detached along the assist line AL by a normal breaking process of adding an external force to the glass substrate 4 to generate a bending moment or the like. Thus, as step S50 (Fig. 2), formation of the crack line CL similar to that of the first embodiment is started (see the dashed arrow in the figure). 10, the assist line AL is formed on the upper surface SF1 of the glass substrate 4, but the assist line AL for separating the glass substrate 4 is formed on the lower surface of the glass substrate 4 SF2). In this case, the assist line AL and the trench line TL cross each other at the position N2 in the plan layout, but do not make direct contact with each other.

The configuration other than the above is substantially the same as the configuration of the above-described first embodiment.

Next, a modification will be described with reference to FIG. In this modification, when the trench line TL is formed in step S30 (Fig. 2), the edge 51 is formed on the upper surface SF1 of the glass substrate 4 with a larger force at the position N2 Is pushed. Specifically, when the position N4 is located between the positions N3 and N2 and the formation of the trench line TL reaches the position N4, the load on the blade tip 51 is reduced. In other words, the load of the blade tip 51 is higher than the position N3 between the positions N1 and N4, which are the start ends of the trench line TL. This makes it easier to cause the formation of the crack line CL from the position N2 while reducing the load at the portion other than the leading end portion.

≪ Embodiment 3 >

In the present embodiment, unlike the first and second embodiments, the trench line TL slides on the upper surface SF1 of the glass substrate 4 in the direction DB instead of the direction DA, Specifically, the following steps are carried out.

Referring to Fig. 14, first, the projection PP and the side portion PS of the blade tip 51 are pushed to the upper surface SF1 at the position N3. 1 (A), the projecting portion PP of the blade tip 51 on the upper surface SF1 of the glass substrate 4 is disposed between the side ED1 and the side PS And the side PS of the blade 51 is arranged between the projection PP and the edge ED2.

Next, the extruded edge 51 is slid on the upper surface SF1 of the glass substrate 4 (see arrows in the drawing). The edge 51 (Fig. 1) is slid onto the upper surface SF1 in the direction DB directed from the side PS to the projection PP. In other words, the nib 51 (Fig. 1) is slid in the direction DB in which the direction from the side PS to the projection PP is projected on the upper surface SF1. The direction DB generally follows the direction in which the extending direction of the side portion PS in the vicinity of the projection PP is projected onto the upper surface SF1. By this sliding, the trench line TL is formed in the same manner as in the first embodiment.

When the trench line TL is formed, in this embodiment, the blade tip 51 is displaced from the position N3 to the position N2 and further displaced from the position N2 to the position N1. That is, referring to Fig. 1, the blade tip 51 is displaced in the direction DB which is the direction from the side ED2 to the side ED1. The direction DB corresponds to a direction opposite to a direction in which the axial direction AX extending from the edge 51 is projected onto the upper surface SF1. In this case, the blade 51 pushes the upper surface SF1 by the shank 52. [

Next, crack line CL is formed in the same manner as in Embodiment 1 (Fig. 5). The extension direction of the crack line CL is the same as that of the first embodiment (broken line arrow in Fig. 5). Therefore, in the present embodiment, the direction in which the crack line CL (FIG. 5) extends (broken arrow in FIG. 5) along the trench line TL (FIG. 14) 14). In order to select the extension direction of the crack line CL as such, the method of forming the trench line TL may be appropriately selected. Specifically, the posture of the blade 51 may be selected as in the first embodiment. According to the study by the present inventor, the extension direction of the crack line CL is mainly determined by the posture of the edge 51, not the formation direction of the trench line TL.

Also in this embodiment, the same modifications as those of the first modification (Figs. 7 and 8) and the second modification (Fig. 9) in the first embodiment are applicable. As in the second embodiment and its modification, the assist line AL may be formed before the trench line TL is formed.

Next, a modified example will be described. First, as in the case of the present embodiment, the trench line TL is formed from the position N3 to N1 via N2 by sliding in the direction DB (FIG. 1) of the blade tip 51. [ Thereafter, in this modification, the sliding of the blade 51 is reversed at the position N1. Then, from the position N1 to the position N2, the blade 41 slides again on the already formed trench line TL. In other words, at the end of the trench line TL formed by the sliding of the blade tip 51 in the direction DB, sliding is again performed in the direction DA of the blade tip 51. [ The crack line CL is extended toward the position N3 from the part of the trench line TL which has been slid again by the edge 51 as a trigger. According to this modified example, it is possible to easily provide the glass substrate 4 with a mechanism in which the formation of the crack line CL is started without particularly requiring the formation of the assist line AL (Fig. 5) or the like . This sliding operation may be performed in the same direction DB from the position N3 to the position N1. However, at the position N1, the cutting edge 51 does not fall from the upper surface SF of the glass substrate 4 Is held in contact with the upper surface SF), it is possible to slide the nib 51 again on the already formed trench line TL from the position N1 to the position N2 .

In this modified example, in the formation of the trench line TL by the sliding of the blade 51, when the portion of the blade 51 to be subjected to sliding again is formed, even if the load of the blade 51 is increased good. More specifically, the load from the position N2 to the position N1 may be higher than the load from the position N3 to the position N2. Thereafter, it is preferable that the raised load is maintained even when the blade 51 slides back from the position N1 to the position N2. This reduces the load on the blade tip 51 in the section other than the section where the blade tip 51 is slidingly overlapped (that is, the section between the positions N1 and N2), and the section where the blade tip 51 is slidingly overlapped It is possible to easily cause the formation of the crack line CL from the crack line CL.

≪ Fourth Embodiment >

15, in the present embodiment, when the trench line TL is formed by sliding in the direction DB (Fig. 1) of the blade tip 51, the blade tip 51 is located at the edge of the glass substrate 4 Passes through a position N0 located on a side ED1. Thus, the edge 51 cuts the edge of the glass substrate 4 at the position N0. With this as an occasion, as shown in Fig. 16, the crack line CL is extended from the position N0 toward the position N3. According to the present embodiment, it is possible to easily impart the glass substrate 4 with a mechanism for starting the formation of the crack line CL without particularly requiring the formation of the assist line AL (Fig. 5) or the like .

The crack line CL can be formed by applying stress to the glass substrate 4 at a predetermined location on the trench line TL by applying stress such as to relax the distortion of the internal stress in the vicinity of the trench line TL do. The application of the stress is not limited to the formation of the assist line AL described in the first to third embodiments or the subsequent separation of the glass substrate or the cutting of the edge of the glass substrate 4 described in the fourth embodiment, For example, application of an external stress by pushing the blade tip again on or near the formed trench line TL, or heating by irradiation with a laser beam or the like can be performed.

<Appendix>

In all of the above embodiments, in the case where the sliding direction of the edge 51 (FIG. 1) in the formation of the trench line TL is the direction DA, (CL) is formed. When the sliding direction of the edge 51 (FIG. 1) in the formation of the trench line TL is the direction DB, the crack line CL is formed in the direction opposite to the direction in which the trench line TL is formed. In any case, if the axial direction AX of the blade edge 51 is more inclined from the normal line direction of the upper surface SF1 of the glass substrate 4, the extension direction of the crack line CL can be reversed have. That is, when the sliding direction of the nib 51 (FIG. 1) in the formation of the trench line TL is the direction DA, the crack line CL is formed in the direction opposite to the direction in which the trench line TL is formed . When the sliding direction of the edge 51 (FIG. 1) in the formation of the trench line TL is the direction DB, the crack line CL may be formed in the same direction as the direction in which the trench line TL is formed have. In this case, it is preferable that the angle AG2 in Fig. 1> the angle AG1.

In addition, the position of stress application to be the instrument for forming the crack line CL along the trench line TL may be selected in consideration of the extension direction of the crack line CL. For example, when the assist line AL is formed as the stress application, the position where the assist line AL crosses the trench line TL is selected in consideration of the extension direction of the crack line CL.

On the basis of the above contents, the method of breaking the glass substrate (brittle substrate) described in the following (1) or (2) can be carried out.

(1) The first brittle substrate cutting method has the following steps a) to c).

a) By causing plastic deformation on one surface by sliding a projection having a projection extending from the projection and a side having a convex shape on one surface of the brittle substrate in a direction from the projection toward the side, Trench lines are formed. The trench line is formed so as to obtain a crackle state in a state where the brittle substrate is continuously connected in the direction crossing the trench line, below the trench line.

b) a crack line is formed by extending a crack of the brittle substrate along at least a portion of the trench line. Below the trench line by the crack line, the brittle substrate is disconnected continuously in the direction crossing the trench line.

c) The brittle substrate is divided along the crack line.

Step a) is carried out such that the direction in which the crackline extends along the trench line in step b) is opposite to the direction in which the trench line is formed.

(2) The second brittle substrate cutting method has the following steps a) to c).

a) By causing plastic deformation on one surface by sliding a projection having a protrusion and a protruding portion and having side portions having a convex shape on one surface of the brittle substrate in a direction from the side portion to the protrusion portion, Trench lines are formed. The trench line is formed so as to obtain a crackle state in a state where the brittle substrate is continuously connected in the direction crossing the trench line, below the trench line.

b) a crack line is formed by extending a crack of the brittle substrate along at least a portion of the trench line. Below the trench line by the crack line, the brittle substrate is disconnected continuously in the direction crossing the trench line.

c) The brittle substrate is divided along the crack line.

The step a) is carried out so that the direction in which the crackline extends along the trench line in the step b) becomes the same as the direction in which the trench line is formed.

4: Glass substrate (brittle substrate)
51: End point
AL: assist line
CL: crack line
SF1: Top surface (one surface)
TL: Trench line
PP: protrusion
PS: Side

Claims (3)

a) generating a plastic deformation on the one surface by sliding a projection having a projection and a side extending from the projection and having a convex shape on one surface of the brittle substrate in a direction from the projection toward the side, And forming a trench line having a groove shape, wherein the trench line is in a cracked state in a state in which the brittle substrate is continuously connected in a direction intersecting the trench line below the trench line And further,
b) forming a crack line by extending a crack in the brittle substrate along at least a portion of the trench line, wherein the brittle substrate under the trench line crosses the trench line Continuous connection in the direction is disconnected,
c) dividing the brittle substrate along the crack line,
The step a) is performed so that the direction in which the crack line extends along the trench line in the step b) is the same as the direction in which the trench line is formed,
Method of breaking a brittle substrate. a) generating a plastic deformation on the one surface by sliding a projection having a projection and a side extending from the projection and having a convex shape on one surface of the brittle substrate in a direction from the side to the projection, And forming a trench line having a groove shape, wherein the trench line is in a cracked state in a state in which the brittle substrate is continuously connected in a direction intersecting the trench line below the trench line And further,
b) forming a crack line by extending a crack in the brittle substrate along at least a portion of the trench line, wherein the brittle substrate under the trench line crosses the trench line Continuous connection in the direction is disconnected,
c) dividing the brittle substrate along the crack line,
Wherein the step a) is performed so that the direction in which the crack line extends along the trench line in the step b) is opposite to the direction in which the trench line is formed,
Method of breaking a brittle substrate. 3. The method according to claim 1 or 2,
The edge has a ridge line formed by the first to third surfaces neighboring to each other, the apex at which the first to third surfaces join together, and the second and third surfaces,
Wherein the projecting portion of the blade edge is constituted by the vertexes and the side portion of the blade edge is constituted by the ridgeline.

Images